Field of the Invention
The present disclosure relates to a photoelectric conversion device and an imaging system.
Description of the Related Art
Metal insulator semiconductor (MIS) photoelectric conversion devices have been proposed as photoelectric conversion devices used for image sensors of cameras. In a photoelectric conversion device illustrated in FIG. 1 in WO2012/004923 (hereinafter referred to as “Patent Literature 1”), a transparent electrode is disposed on top of a photoelectric conversion film, and a pixel electrode is disposed beneath the photoelectric conversion film. An insulating film is disposed between the photoelectric conversion film and the pixel electrode. Patent Literature 1 describes enabling of correlated double sampling with the configuration described above, achieving noise reduction.
Japanese Patent Laid-Open No. 2011-228621 (hereinafter referred to as “Patent Literature 2”) discloses that a compound semiconductor, a silicon crystal, an ionic crystal, or the like is usable for a photoelectric conversion film. Patent Literature 2 describes a photoelectric conversion film formed of a material with a high optical absorption coefficient, such as amorphous silicon or an organic material. According to Patent Literature 2, the use of such a material leads to an increase in sensitivity.